Pakistani President Asif Ali Zardari urged the United States and NATO Friday to help stop shipment of arms and ammunition from Afghanistan into Pakistan.

He made the demand in his separate meetings with U.S. Secretary of State Hillary Clinton and the NATO Secretary General Anders Fogh Rasmussen, in New York.

The demand came the same day when Pakistani media reported that security forces foiled an attempt to smuggle arms from Afghanistan into Bajaur tribal region of Pakistan.

Both Afghanistan and Pakistan have, for quite some time, been trading charges regarding infiltration of militants and shipment of arms and ammunition into each other's territories.

Pakistan though has never directly accused the Afghan government of fomenting trouble on its border, yet it claims that insurgents functioning in its volatile northwestern areas are receiving arms supplies and manpower from their counterparts in Afghanistan.

For its turn, the Kabul government alleges that Taliban militants are using Pakistani tribal territories as a springboard for their activities inside Afghanistan.

The U.S. and NATO forces in Afghanistan also claim that militants hiding in the Pakistani areas are responsible for attacks on international forces.

U.S. Secretary of State Hillary Clinton claimed the other day that the border areas between Afghanistan and Pakistan are serving as an epicenter of terrorism.

In a statement in New York, she said: "The U.S. government is trying to protect allied troops (in Afghanistan) from terrorists hiding in the Pakistani border areas."

Afghan government says that Sirajuddin Haqqani, a powerful Taliban commander in eastern Afghanistan, has set up bases in Pakistan's North Waziristan region.

They allege that the Afghan commander is securing active support from the Pakistani Taliban factions of Mulla Nazir and Hafiz Gul Bahadur.

U.S. drones have carried out a number of missile strikes against Haqqani's alleged bases and hideouts in North Waziristan over the last two years.

In one attack, the pilotless American planes also destroyed a seminary run by the Afghan commander in Dandi Darpakhel area close to the border.

Just on Wednesday, 12 persons, all Afghan civilians, were killed in a similar attack in the same area.

Pakistan and Afghanistan share a 2,640-kilometer long border, which mostly passes through rugged and inaccessible terrain inhabited by less than a million unruly semi-independent Pashtoon tribes.

Ever since the commencement of the US-led war against Taliban and al-Qaeda insurgents in Afghanistan, Islamabad has deployed 100,000 troops and established over 1,000 border check posts along the border to check the entry of militants from its soil into Afghanistan.

It has also installed biometric devices at the Torkham and Chaman border-crossings to ensure that no illegal crossing of the border takes place.

However, while Pakistan says it has taken all steps to block infiltration of subversive elements to and from Afghanistan, it has repeatedly asked NATO forces and the Afghan government to seal the border on their side to check illegal border-crossing.

As Afghanistan and the international forces are alleging infiltration of miscreants from Pakistan, Islamabad also alleges that insurgencies in its restive North West Frontier Province (NWFP) and the Federally Administered Tribal Areas (FATA) are being stoked from across the Afghan border.

During the recent military operation against militants in Swat and Malakand areas, the Pakistani security forces had captured weapons, which carried marks of Western countries.

According to Pakistani officials and media analysts, these were the weapons, which the Taliban militants had stolen from the international forces in Afghanistan.

In the past, there have been reports that the Pakistani and Afghan Taliban had looted truckloads of arms and ammunition from NATO supply convoys passing from Pakistan to Afghanistan.

Reports have also appeared in recent days that after their defeat at the hands of the Pakistani security forces in Malakand, Bajaur and Mohmand regions, the Pakistani militants have fled to Afghanistan.

The Kabul-Based Rah-e Nijat daily reported last week that hundreds of Pakistani Taliban have infiltrated into the Afghan territory, forcing their way into Balkh, Kunduz, and Faryab provinces of the relatively peaceful northern Afghanistan.

On the other hand, Pakistani officials and media allege that anti-social elements and militants on the Afghan side of the border are involved in incidents of abduction for ransom inside the Pakistani territory.

Professor Athanasius Lerounis, a Greek social scientist and volunteer, involved in research activities in Chitral district of Pakistan, was abducted and shifted to Afghanistan's Nuristan province earlier this month.

Despite repeated appeals and diplomatic maneuvers, the abductors are reluctant to release him without the payment of 2 million U.S. dollars of ransom.